Laying of moored mines from submarines



H. B. PRATT LAYING 0F MOORED MINES FROM SUBMARINES Filed Dec. 26, 1929 4 Sheets-Sheet I I 7 ..,.....1..W.@ 0.

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Oct. 7, 1930. V H] PRATT 1,777,416

LAYING 0F HOORED MINES FROM SUBMARINES Fi led Dec'. 26, 1929. 4 Sheets-Sheot 2 '57 I [9% 71 Q -I 176' I .\II1 1/1 11/ Oct. 7, 1930. PRATT 1,777,416 7 j LAYING OF IOORED MINES FROM SUBIARINBS Filed Dec. 26. 1929 4 Sheets-Sheet, 3

Oct. 7, 1930. H. B. PRATT 1,777,416

LAYING OF MOORE!) MINES FROM SUBMARINES Filed Dec. 26, 1929 4 Sheets-Sheet 4 Patented Oct. 7, 1930 men sr rEs ATEN r orrrcs Y HARTLEY BLYTH PRATT, OF WESTMINSTER, LONDON, ENGLAND, ASSIGNO R TO VICKERS-ARMSTRONGS LIMITED, OF LONDON, ENGLAND, A BRITISH COMPANY LAYING OF M OORED MINES FROM SUBMARINES Application filed December 26, 1929, Serial No.

for laying by suitable mechanism operated from the interior of the submarine. In such a system of laying, the hydrostatic depth setting devices 'ofthe mines cannot be altered from the interior of the submarine after the mines have been placed in position in the open laying. tubes or chambers, so that the depth setting devices must be finally set before the mines are placed in the" tubes or chambers and the submarine departsfor its objective. It is however very desirable to be able to regulate'the depth setting devices after the mines have been placed in position in the tubes or chambers-as the tactical obj ective of the mineslmay not be known when they are placed in the tubes or Chambers or may subsequently be changed, or the mines may require tobe laid in av locality where there isa large rise and fall ofsea level due to tides in; which event'it'may not be possible to know'at the time when the mines are placed in the tubes or chambers theparticular'state of the tide at thetimewhen the mines will be laid. I

According to the present] invention the regulation of the hydrostatic clepth s'etting devices of the mines is effected whenthe latter are in position in the open laying tubes or chambers, by means of 'leompressed air controlled from-aposition withinthe submarine.

When the mines are placed inthe laying tubes or chambers of the submarine the chambersof the hydrostaticdep'th' setting devices are connected'bymeans of 'a length of external tubing to a'suitableconnection which passes through the ipressure hull of the submarine andis connected to -tubing withinthe submarine whichlatter tubing is led to the controlpos'ition 'and is supplied with "compressed air, Itis evident that by raising or lowering the pressure ,of the air by suitablemean's at the control position the hydrostatic depth setting devi'cesican be ad} justed to regulate the depth setting of. the

' mines within the range-of the'sa'id device's.

416,539, and in Great Britain March 16, 1929.

After the pressure in the hydrostatic de- ,vices has been adjusted to a degree corresponding to the desired mine depth setting, a valve inside the pressure hull is closed so as to' cut off the supply of compressed air. A suitable isolating valve may be fitted on each mine between the hydrostatic device and the aforesaid external tubing so that when a mine is dropped from the laying tube the'following actions occurz-(l) After the mine i'sreleased and drops a short distance a lever appertaining to the isolating valve engages a projecting piece in" the laying tube in order to cause the valve to close and cut off communication to the hydrostatic device and (2) after the mine has dropped a further suitable distance the ex ternal tubing is disconnected from the casing of the isolating valve and the mine then dropsfreely. V

The hydrostatic depth setting device on each mine may also have a mechanical setting so that a depthregulation may bejmade before placing, the mines in the laying tube or chamber. In this manner, if the mines are required to be laid in tidal waters and the required depth settings are decided be- "foreh-anchthe hydrostatic devices'can be adjusted'mech'anically for a depth setting corresponding to the "low tide water level at the 'desired localitv ,The compressedair system is then only'required to be used to give an equal increased depth settingto all the mines correspondingl'tothe height of the actual water level, at the time of laying, above low tide water level. In order that the said invention may be clearly'understood and readily carried into effect, the same will now be described more fully with reference to-the accompanying of the pressure hull, B the laying tube or a chamber which is open to the sea, and C one of the mines situated within this chamber and normally supported by a stop member D as shown in Figure 1. When this stop member is moved into its disengaging position (Figures 2 and 3) the mine vfalls by gravity from the chamber B.

E represents the casing of the hydrostatic depth setting device (details of which will be hereinafter described) .which risicarried by the mineand is regulated byi-compressed air admitted through a pipe E This pipe communicates with the casing F ofan isolating valve (details of which will also be hereinafter described) controlled by alever F arranged above a stop member B in the chamber B. The said valve casingiiFhas detach ablyconnectedthereto a length of armoured flexible tubing F the upperend of which is attached to a connection F which passes through the pressure hull A and is connected to tubing F within the submarine, the latter tubing being led to the control position and being supplied .with compressed air which thus has access tothe hydrostaticrlepth setting device E. After the pressure in the said device has been adjusted to ,a degree corresponding to the desired mine depthsetting as indicated ,bya pressure gauge F (Figure 4) a stop valve F (Figures 1 to 3) inside the pressurehull is closed so ,as 010,111 off the supply of compressed air. The hydrostatic depth setting device is thus set and the mine is ready to be released. After release takes place and the mine commences to drop the lever F strikes against the stop memberB and the said lever is thereby moved from the position shown Figure 1 to the position shown in Figure 2, thereby causing the isolating valve in the casing F to be closed in the manner hereinafter described so as toout off communication between the tubing F and the pipe E leading to the casing of the hydrostatic device E so that a predetermined pressure is maintained within the latter; the said valvealsopreventssea water from entering the casing of the hydrostatic device. A fter the min e has dropped afurther suitable distance thetubing F ispulledzaway from the valve casing Fin the manner hereipafter described and themineihen drops freely. It will be understoodthat although only one mine has been referredto there will be sev eral, each provided with the devices herein described. r

- Referring to Figure 4 the hydrostatic depth setting device Eissimilar in its broad aspecttothat forming the subject of English PatentNo. 264.973 that is to say it comprises drum E rotatably mounted within the Gasing-E and carrying an auxiliary-wire Eicon nected to the contrivance situated ,inthe anchor for stopping thepaying out of the mooring cable by the pull which is exerted s onthe said auxiliary .wire when the rotation of the drum is stopped by a locking pawl E which is moved into engagement with a lug E on the side of the drum E when the set depth is reached, this depth being determined by a diaphragm E one side of which is open to the sea and theother is acted upon by the airpressure supplied by thevpipe E The said pawl E forms part of a lever Fl which is pivotally carried by a rod E con- :nected to the diaphragm E and-is acted upon by a spring E In addition to the compressed air setting of the hydrostatic device a-mechanical setting is provided so that regulation may be ,made before placing the mine in thelaying tube as hereinbefore mentioned. For this purpose a movable fulcriunE 1s provided between thepivot of the lever E and the pawl E and the contiguous portion of this lever is graduated as shown to :correspond with diiferent depth settings. moving the fulcrum E towards or away from the pivot the time at which the pawl E is moved into eng ement with the lug a1n- .der the conjoint action of the spring Fi i the external sea pressure and the internal; air pressure can be varied. Tl1'1S,'?LS hereinbefore referred to, enablesa preliminary-depth 7 setting to be effected; by :mov-i ngthe :fulcnusn lE-"in accordance with the low tide water level at the locality where it is desired to lay the minesand the compressed air regulation is then only required to be used torgiye an equal increased depth set-tingnto all-the mines corresponding to the height of the ac tual ,waterlevel above low tide water level at the time oflaying.

Theisolating valve casing F contains a spring controlled valve F of disc shape adapted to bear against a valve seat situated between the compressed air inlet opening communicating with the tubing F and the on the valvecasing F in such a manner'that 5 this gland will becornepulled fromzthe socket when the mine falls 'beyondthe point at which the lever F *isoperated'to allow the valve F to move onto its seat.

The above described method of regulating 1 the depth setting of'mines'in open tubes or chambers by means of compressed air-avoids the difiiculties which would result from the use of mechanical connections for the depth setting devices :of the .mines, since, such we chanical connections must pass through the pressure hull of the submarine and requirea number of water-tight glands; moreover such an arrangement of mechanical connections would occupy more space than is desirable inside the submarine.

It is to be understood that the present invention relates only to cases where the submarine mines are carried in laying tubes or chambers which are open to the sea, as in an alternative system of mine laying from submarines in which the mines are carried inside the pressure hull and are launched in a similar manner to that employed for launching submerged torpedoes, the depth setting of the mines can be regulated directly by the personnel of the submarine up to the actual moment of laying the mines.

What I claim and desire to secureby Letters Patent of the United States is 1. In a submarine, the combination of mine laying tubes or chambers which are open to the sea and from. which mines provided with hydrostatic depth setting devices are dropped, mechanism operated from the interior of the submarine for releasing said mines and means for regulating the depth setting devices of the mines from the interior of the submarine when the mines are in position in the said open laying tubes or chambers.

2. In a submarine, the combination of mine laying tubes or chambers which are open to the sea and from which mines provided with hydrostatic depth setting devices are dropped, mechanism operated trom'the interior of the submarine for releasing said mines and compressed air means for regulating the depth setting devices of the minesfrom the interior of the submarine when the mines are in position in the said open laying tubes or chambers.

3. In a submarine, the combination of mine laying tubes or chambers which are open to the sea and from which mines provided with hydrosatic depth setting devices are dropped, mechanism operated from the interior of the submarine for releasing. said mines, compressed air means for regulating the depth setting devices of the mines when the latter are in position in the said open laying tubes or chambers, and means for regulating the pressure of the compressed air from the in terior of the submarine.

4. In a submarine, the combination of mine laying tubes or chambers which are open to the sea and from which mines provided with hydrostatic depth setting devices are dropped, mechanism operated from the. interrior of the submarine for releasing said mines, lengths of external tubing connected to the chambers of the hydrostatic depth setting devices of the mines, a connection'which passes through the pressure hull of the submarine and to which the external tubing is connected and tubing within the submarine connected to said connection and led to a control position within the submarine, the last I mentioned tubing containing air under pressure.

5. A submarine mine for use in a submarine as claimed in claim 4 comprising an isolating valve associated with the hydrostatic depth setting device and means for detachably connecting the external tubing to the casing of said isolating valve, this isolating valve being operated to cut off communication to the hydrostatic depth setting device as the mine commences to descend in the laying tube or chamber.

6. In a submarine mine the combination with the elements claimed in claim 5, of mechanical'means for setting the hydrostatic depth setting device in addition to the setting provided by the compressed air.

7. A submarine mine provided with a hydrostatic depth setting device which is adjusted by means of compressed air, a conduit leading to the interior of the chamber of said depth setting device, an isolating valve the casing of which communicates with said conduit, a second conduit leading compressed air into said isolating valve and meansfor moving said valve, when released,

to its closed position so as to shut 0E communication to the interior of the hydrostatic depth setting device chamber.

8. A submarine mine provided with a hydrostatic depth setting device which is adjusted by means of compressed air, additional mechanical means for adjusting said device, a conduit leading to the interior of the chamber of said depth setting device, an isolating valve the casing of which communicates with said conduit, a second conduit leading compressed air into said isolating valve and means for moving said valve, when released, to its closed position so as to shut ofi communication to the interior of the hydrostatic depth setting device chamber.

H. B. PRATT. 

